The invention relates to a treatment of herpes simplex and more particularly to a topical treatment of herpes simplex.
Herpes simplex is a virus which exists on the skin in the form of lesions. There are two types of herpes simplex: Type 1 and Type 2. Type 1 herpes are more commonly known as fever blisters and are usually caused by excessive sun, upper respiratory infections and the like. Type 2herpes are sexually-transmittable lesions located about the genitalia. Many people cannot manufacture a sufficient amount of antibodies to the herpes simplex virus, therefore the virus resides in their ganglia, and these people suffer from recurrent herpes simplex. Due to the very high incidence of herpes simplex in the world and the devastating nature of the virus, a large number of treatments for herpes simplex have been advocated.
In early studies, beneficial results were obtained when topical applications of 0.5% and higher concentrations of zinc sulfate solution were used in the treatment of herpes simplex infections. Due to indications that zinc was effective in the treatment of herpes simplex, zinc tablets were put on the market in the mid 1970's. Unfortunately, there was only a slight absorption of these tablets through the gut and not enough zinc was distributed to the herpetic sites to do any good. Experiments in the second half of the 1970's proved that zinc was indeed effective in the treatment of herpes simplex, since they showed that zinc interfered with the multiplication of the herpes virus at a specific point. Experimental investigations in vitro showed that zinc ions irreversibly inhibited replication of herpes simplex virus Type 1 BSC-1 cells by selective inhibition of herpes simplex virus Type 1 DNA polymerase.
In "Topical treatment of recurrent herpes siplex and posttherapeutic erythema multiforme with low concentrations of zinc sulfate solution", British Journal of Dermatology, (1981) pp. 191-194, Brody discloses the topical use of low concentrations of zinc sulfate solution (ZnSO.sub.4.7H.sub.2 O) fo recurrent herpes simplex of the skin and oral mucous membrane. Even though the Merck Index (1968) recommended 0.2-1% zinc sulfate solution for the topical treatment of herpes simplex, Brody suggests that no more than 0.025-0.05% zinc sulfate should be used for the skin as compresses and 0.01-0.025% for the mucous membrane as rinses. Brody states that the concentrations recommended in the Merck Index are too strong and cause severe irritation, an unpleasant dryness of the skin and mucous membrane, and a strong emetic reflex. These side effects are not provoked by the low concentrations of the zinc sulfate solution that Brody uses. Brody found that immediate treatment followed by weekly to monthly maintenance treatment with the low concentrations of zinc sulfate solution prevented a relapse in all patients of recurrent herpes simplex on the skin and oral mucous membrane during an observation period of 16-23 months.
Although there have been many proposed treatments for herpes simplex which employ zinc, none of these treatments have been able to stop the itching, burning, and stinging symptoms associated with the virus in 24 hours or less, clear the lesions in approximately 5 days, and at the same time, cause no unpleasant side effects.